Aldimine surface quality enhancers

Abstract

This invention is the addition of an aldimine to enhance the ability of thermoplastic low profile additives to improve the surface quality of cured sheet molding compound vehicle parts.

I claim: 
     
       1. In a thermosetting polyester resin composition for use in sheet molding compound comprising unsaturated polyester resin,   unsaturated monomer, and   low profile additive,   the improvement comprising the addition of an effective proportion of an aromatic aldimine surface quality enhancer.   
     
     
       2. The composition of claim 1 wherein said aldimine is made by condensation with water cleavage from trimethylol propane tris ether and benzaldehyde. 
     
     
       3. The composition of claim 1 wherein said aldimine is made by condensation with water cleavage from diprimary amine of dimer acid and benzaldehyde. 
     
     
       4. The composition of claim 1 wherein said aldimine is made by condensation with water cleavage from isophorone diamine and benzaldehyde. 
     
     
       5. The composition of claim 1 comprising 4 to 6 parts aldimine in 100 parts resin, monomer and low profile additive. 
     
     
       6. The composition of claim 5 comprising 5 parts aldimine. 
     
     
       7. The composition of claim 1 wherein said low profile additive is a thermoplastic low profile additive selected from the group consisting of saturated polyester, polyurethane, and polymethyl methacrylate, polystyrene, and epoxy-extended polyester. 
     
     
       8. A part made by heating under pressure a molding compound comprising unsaturated polyester resin, styrene, low profile additive, and an aromatic aldimine. 
     
     
       9. The part of claim 8 wherein said sheet molding compound further comprises a hydroxyl functional acrylate compound. 
     
     
       10. The part of claim 9 wherein said compound is hydroxyl methacrylate. 
     
     
       11. The part of claim 9 wherein said compound is hydroxypropyl methacrylate. 
     
     
       12. The part of claim 8 wherein said aldimine is made by condensation with water cleavage from trimethylolpropane tris ether and benzaldehyde. 
     
     
       13. The part of claim 8 wherein said aldimine is made by condensation with water cleavage from diprimary amine of dimer acid and benzaldehyde. 
     
     
       14. The part of claim 8 wherein said aldimine is made by condensation with water cleavage from isophorone diamine and benzaldehyde. 
     
     
       15. The part of claim 8 comprising 4 to 6 parts aldimine in 100 parts resin, monomer and low profile additive. 
     
     
       16. The part of claim 15 comprising 5 parts aldimine.